1952-08-14	1961-10-01
1961-10-01	1972-04-03
1972-04-03	1984-10-10
1984-10-10	1992-03-14
1992-03-14	1992-12-12
1992-12-12	1997-05-08
1997-05-08	1997-11-23
1997-11-23	2000-01-03
2000-01-03	null
1957-12-10	1968-02-03
1968-02-03	1981-03-14
1981-03-14	1989-02-02
1989-02-02	1995-10-09
1995-10-09	1999-01-03
1999-01-03	null
